One of the most decisive factors influencing the reduction of cost in the development of new types of piston machines at present is the reduction of time required for their tests during the research and development period. Not least important is the problem of prolonging the service life of machines. The use of apparatus enabling an operative measurement of performance parameters contributes to the cost reduction in the development of new types of machines and makes it possible to control machine performance to optimize it.
Known in the art is an apparatus for measuring parameters of work diagram of piston machines (cf. U.S. Pat. No. 3,375,711, Apr. 1968), comprising an angular mark sensor having uniformly distributed crankshaft rotation angle marks and a top dead center mark, the output of the sensor being coupled to a crankshaft angular position pulse former and a top dead center pulse former, n sensors sensing pressure in cylinders of piston machines, the output of one sensor, in accordance with the cylinder selected for indication, being coupled to an amplifier converter handling a pressure signal from the cylinder of a piston machine, and a widthpulse converter having a first input connected to the amplifier converter handling the pressure signal from the cylinder of a piston machine, and also comprising a main coincidence gate having a first input coupled to a reference oscillator and a second input coupled to the width-pulse converter, and an analysis and control unit having a flip-flop operatively coupled to the crankshaft angular position pulse former and to the top dead center pulse former, and a counter having its input coupled to the output of the main coincidence gate. In addition, the apparatus comprises a pulse former forming signals of equal increments of a piston machine working volume, a pulse former of forming signals of change in equal increments of piston machine cylinder volume, a lower dead center signal former, having their inputs coupled to respective outputs of the angular mark sensor, and the outputs, to the analysis and control unit, and the angular mark sensor also has uniformly distributed equal cylinder volume increment marks, marks of a change in increments of the cylinder volume and a bottom dead center mark.
It should be, however, noted that in the above-described apparatus the angular mark sensor is provided for measuring parameters of work diagram of only one cylinder of a piston machine. When changing over for measurement of parameters of work diagram of another cylinder, the machine should be stopped, and the sensor should be re-installed thus reducing the productivity in measuring parameters of work diagram during tests and excluding the possibility of using the apparatus for control, diagnostics and automation of performance control in multicylinder machines.